Following Radar’s exclusive report that Jon won temporary custody of troubled son Collin, 14, this week, an insider claimed the shocking court decision was made possible when a third party, the guardian, intervened to look out for his best interest.

“Once an ad litem was assigned, the judge ruled both Hannah and Collin should be in the custody of Jon,” the insider explained.

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As Radar first reported, Collin’s sister Hannah, also 14, moved in with Jon earlier this year, following a nasty war between Jon and Kate.

Over the summer, Jon revealed the news to his fans in an Instagram live session.